Methods and flexographic printing plates are already known. A known method for production of a flexographic printing plate consists of insolating with ultraviolet light a photo-polymer of elastomeric nature through a mask which is opaque with respect to ultraviolet (UV) light. This method has the disadvantage that the mask is produced digitally by selective ablation in situ of a surface layer which is opaque with respect to UV with a laser operating with infrared light.
According to another method, the image is produced by direct writing of the photo-polymer plates using amplitude modulated ultraviolet sources. These sources can be lasers typically operating at wavelengths of 350 to 370 nm. These sources have the major disadvantages of having an exorbitant cost, of having a low energy efficiency and also low available power, of using optics with power losses and of being expensive to maintain.
Yet another known method involves the use of photo-polymers which are sensitive to visible light with, for example, silver base technologies in the manner of photography films. This method is very limiting because it requires strict measures of protection against daylight.